Social media posts distort 2018 Greta Thunberg tweet

To some people online, June 21 was "Greta Thunberg Day."

Some social media posts suggested it was the day she had predicted the world would end. 

"Greta Thunberg’s beginning of the end of the world prediction was for today, June 21st," read a screengrab of a headline shared by Donald Trump Jr., among others.

In the picture, Thunberg leans her face in her hand with a look of disappointment. "Happy Greta Thunberg day to all who celebrate," reads text across the image. 

"The day is young folks … there’s still time," Trump Jr. quipped in his caption on his June 21 Instagram post.

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The image in the post came from a June 21 Breitbart story about something Thunberg tweeted in 2018.

So what happened? 

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On June 21, 2018, Thunberg tweeted a link to a February 2018 article from a site called Grit Post, which was once described as "real news for the working class" and no longer seems to exist. Thunberg quoted the story verbatim in her tweet, writing: "A top climate scientist is warning that climate change will wipe out all of humanity unless we stop using fossil fuels over the next five years." 

Both Thunberg’s tweet and the Grit Post story have since been deleted. 

That could be because James Anderson, a Harvard University atmospheric chemistry professor and the "top climate scientist" referred to in the Grit Post story, later said he never warned that climate change would wipe out all of humanity unless humans stop using fossil fuels by a specific date. 

"The ‘wiping out of humanity by 2022’ is a total distortion of what I said or meant" during a 2018 speech, he told The Associated Press in March 2023. 

That means that two things are wrong in these posts.

First, Thunberg’s original tweet didn’t predict that the world would end on June 21, 2023, as social media posts suggested. Rather, it said that a scientist had warned of humanity’s eventual demise if humans didn’t stop using fossil fuels within five years. 

Second, that scientist later said reports were wrong that he claimed climate change will wipe out humanity unless we stop using fossil fuels over the next five years.

We rate claims that Thunberg predicted humanity would be wiped out on June 21, 2023,  False.